package cn.chen.miaosha.redis;

import com.alibaba.fastjson.JSON;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

@Service
public class RedisService {

    @Autowired
    JedisPool jedisPool;

    /**
     * 获取单个对象
     * @param prefix
     * @param key
     * @param clazz
     * @param <T>
     * @return
     */
    public <T> T get(KeyPrefix prefix,String key,Class<T> clazz){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            //生成真正的key
            String realKey = prefix.getPrefix() + key;
            String str = jedis.get(realKey);
            T t = stringToBean(str,clazz);
            return t;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 设置对象
     * @param prefix
     * @param key
     * @param value
     * @param <T>
     * @return
     */
    public <T> boolean set(KeyPrefix prefix,String key,T value){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String str = beanToString(value);
            if(str == null){
                return false;
            }
            //生成真正的key
            String realKey = prefix.getPrefix() + key;
            int seconds = prefix.expireSeconds();

            if(seconds <= 0) jedis.set(realKey, str);
            else jedis.setex(realKey,seconds,str);

            return true;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 增加值
     * @param prefix
     * @param key
     * @param <T>
     * @return
     */
    public <T> Long inc(KeyPrefix prefix,String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.incr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 减少
     * @param prefix
     * @param key
     * @param <T>
     * @return
     */
    public <T> Long dec(KeyPrefix prefix,String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.decr(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 删除
     * @param prefix
     * @param key
     * @return
     */
    public boolean delete(KeyPrefix prefix,String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.del(realKey) > 0;
        }finally {
            returnToPool(jedis);
        }
    }

    /**
     * 判断是否存在
     * @param prefix
     * @param key
     * @param <T>
     * @return
     */
    public <T> boolean exists(KeyPrefix prefix,String key){
        Jedis jedis = null;
        try {
            jedis = jedisPool.getResource();
            String realKey = prefix.getPrefix() + key;
            return jedis.exists(realKey);
        }finally {
            returnToPool(jedis);
        }
    }

    public static <T> String beanToString(T value) {
        if(value == null){
            return null;
        }
        Class<?> clazz = value.getClass();
        if(clazz == int.class || clazz == Integer.class){
            return  ""+value;
        }else if(clazz == String.class){
            return (String)value;
        }else if(clazz == long.class || clazz == Long.class){
            return ""+value;
        }else{
            return JSON.toJSONString(value);
        }
    }

    @SuppressWarnings("unchecked")
    public static <T> T stringToBean(String str,Class<T> clazz) {
        if(str == null || str.length() <= 0 || clazz == null){
            return null;
        }
        if(clazz == int.class || clazz == Integer.class){
            return  (T)Integer.valueOf(str);
        }else if(clazz == String.class){
            return (T)str;
        }else if(clazz == long.class || clazz == Long.class){
            return (T)Long.valueOf(str);
        }else{
            return JSON.toJavaObject(JSON.parseObject(str), clazz);
        }
    }

    private void returnToPool(Jedis jedis) {
        if(jedis != null){
            jedis.close();
        }
    }

}
